Signal switching device

ABSTRACT

A signal switching device with a plurality of each of first and second groups of rectangular parallelopiped switching units arranged in X,Y, and Z directions. A plurality of first groups of spaced parallel conductors are disposed in said X direction in respective spaced X-Z planes of said first group units for multiply connecting of break terminals of corresponding switches in said respective first group unit stacks. A plurality of second groups of spaced parallel conductors are disposed in said Y direction in respective Y-Z planes for multiply connecting make terminals of corresponding switches of said second group units in said Y-Z planes. Input signal lines are disposed in parallel and connected to break terminals of said switches in respective first group units in said X-Z planes, while output signal lines are disposed in parallel and selectively connected to make terminals of switches of the second group units in the Y-Z planes, whereby a desired one of the input lines is connectable to a desired one of said output lines.

Shinohara et a1.

[ 1 Oct. 17, 1972 [54] SIGNAL SWITCHING DEVICE [72] Inventors: Takeo Shinohara; Yoshikazu Miyamoto, both of Tokyo, Japan [73] Assignee: Nippon Electric Company, Limited,

Tokyo, Japan [22] Filed: March 24, 1971 [21] Appl. No.: 127,498

[30] Foreign Application Priority Data March 27, 1970 Japan ..45/26379 [52] U.S. Cl. .....200/175, 335/112, 335/152 [51] Int. Cl. ..H0lh 67/30 [58] Field of Search ..200/175, 176; 335/108, 109, 335/112, 152, 151; 317/113 [56] References Cited UNITED STATES PATENTS 3,293,502 12/1966 Beierle ..335/152 X 3,249,714 5/1966 Hyink et a1. ..335/151 2,901,547 8/1959 Miloche 335/108 X 3,500,267 3/1970 Wasserman ..335/112 3,523,262 8/1970 Bernutz et al. ..335/112 3,030,451 4/1962 Jacobson ..335/152 Primary Examiner-Robert K. Schaefer Assistant Examiner-Robert A. Vanderhye Attorney-Mam & Jangarathis [57] ABSTRACT A signal switching device with a plurality of each of first and second groups of rectangular parallelopiped switching units arranged in X,Y, and Z directions. A plurality of first groups of spaced parallel conductors are disposed in said X direction in respective spaced X-Z planes of said first group units for multiply connecting of break terminals of corresponding switches in said respective first group unit stacks. A plurality of second groups of spaced parallel conductors are disposed in said Y direction in respective Y-Z planes for multiply connecting make terminals of corresponding switches of said second group units in said Y-Z planes. Input signal lines are disposed in parallel and connected to break terminals of said switches in respective first group units in said X-Z planes, while output signal lines are disposed in parallel and selectively connected to make terminals of switches of the second group units in the Y-Z planes, whereby a desired one of the input lines is connectable to a desired one of said output lines.

1 Claim, 18 Drawing Figures PATENTEDncI 11 m2 SHEU 2 0F 6 a INVENTORS Tokeo Shinoharc Yoshikozu Miyomoto BY 772mm ATTORNEYS PATENTEDnm 11 1912 SHEU t Of 6 INVEHTQFS Tokeo Sninoharc Yoshikozu Miyornoto BY 7]Za/zm,&

, ATTORNEYS PATENTED um I 7 m2 SHEET 6 BF 6 Fig. 17.

Fig. IB.

INVENTORS Tokeo Shinohoru Yoshikczu Miyornoto 772mmiszjam waatlw ATTORNEYS SIGNAL SWITCHING DEVICE This invention relates to signal switching devices of the kind for establishing connections, for example, between one of a plurality of inlets and one of a plurality of outlets. This invention admits of suitable application with electronic computers, data or information processing equipment, information switching equipment, and the like.

In conventional signal switching devices wherein signal transmission paths are selectively established, it is desirable that the number of switching elements included therein be kept to a minimum. To fulfill this purpose, it has been common to provide a plurality of input signal lines, hereinafter inlets, and a plurality of output signal lines, hereinafter outlets, disposed so as to orthogonally intersect each other and to provide a plurality of signal switching matrices, each having its basic unit comprised of switching elements capable of bridging across an inlet and an outlet at each intersecting crosspoint, which matrices are interconnected in linkage form. Stated more specifically, switching stages, each containing a plurality of signal switching matrices, may comprise a primary switching stage to which the inlets are connected, a plurality of intermediate switching stages, and a final switching stage to which the outlets are connected, all stages being interconnected in linkage form.

The switching capacity of each signal switching matrix, which may comprise a crossbar switch, is limited by the predetermined numbers of inlets and outlets included therein. The provision of only a few predetermined kinds of matrices differing in capacity, even though the matrices are suitably combined, does not result in an economical structure containing a minimum number of crosspoints or switching elements. In other words, conventional switching matrix designs lack sufficient versatility for constructing signal switching devices therefrom having varying capacities. Conversely, the preparation of many individual kinds of signal switching matrices is not preferred because the benefits that were formerly derived from the mass production of fewer kinds of components are sacrificed. Furthermore, since linkage connections between two signal switching matrices invariably produce points of intersection, mechanical or automatic wiring cannot be adopted and therefore, manual soldering or wrapping work must be utilized to execute the vast number of requisite wiring operations. This results in low manufacturing efficiencies and high manufacturing costs. In addition, since the linkage connections intersect one another, linkage wires tended to become long, and crosstalk of switched information signals is increased. Therefore, conventional devices comprised of such matrices are not suitable for operating on signals containing comparatively high frequency components, such as video signals.

Therefore it is an object of this invention to provide a most economical signal switching device comprised of segments of the same geometry, said segment being the basic unit of the device irrespective of the device switching capacity.

Another object of the invention is to provide a most economical signal switching device comprised of a plurality of segments of the same geometry and having a minimum number of switching elements.

Still another object of this invention is to provide a signal switching device wherein linkage connections do not include points of intersection in any plane.

An additional object of this invention is to provide a signal switching device that admits of facile manufacture and may be produced by automatic fabricating techniques.

A further object of the invention is to provide a broad-band signal switching device with as small crosstalk attenuation as possible.

According to this invention, 1, m, and n segments (1, m, and n each being a positive integer equal to or larger than unity), each segment comprising P (P being a positive integer equal to or larger than unity) signal switching elements, are disposed successively along the X, Y, and Z rectangular coordinate axes so as to form a three-dimensional array. According to one kind of segment, the terminals of an array of switching elements included therein are disposed in the same direction on each of two spaced parallel surfaces of the segment. In accordance with another kind of segment, the terminals of an array of switching elements included therein are disposed in the same direction on each of two adjacent perpendicular surfaces of the segment. in accordance with still another kind of segment, auxiliary terminals of an array of switching elements included therein are connected to respective terminals disposed on one of the two spaced parallel surfaces of the segment and, in addition, the auxiliary terminals are disposed in the same direction on either surface perpendicular to said two spaced parallel surfaces. The switching device thus formed includes a input signal lines, hereinafter inlets, (a being a positive integer equal to or larger than 1) each of which inlets may admit of multiple connection with the terminals of an array of switching elements included in a segment, said a inlets being disposed, for example, in the X direction; b output signal lines, hereinafter outlets (b being a posi tive integer equal to or larger than 1), each of which outlets may admit of multiple connection with the terminals of an array of switching elements included in a segment, said b outlets being disposed, for example, in the Y or Z direction; and c interconnection means (0 being a positive integer equal to or larger than 1), each of which may admit of multiple interconnection between terminals associated with those terminals of an array of switching elements included in a segment to which the inlets are connected and with terminals associated with those terminals of an array of switching elements included in a segment to which the outlets are connected said interconnection means extend, for example, in the Z or Y direction.

More specifically, the three-dimensional structure of segments as above-mentioned may be regarded as consisting of a plurality of segment groups which are divisible in any one direction, such as, for example, the Z direction, such that, when any two groups to be switched are taken into consideration, the inlets are associated with one group and the outlets are associated with the other group, and linkage wires are connected between the two groups. It thus becomes possible with such a structure to freely select the signal switching capacity thereof by suitably determining the number of segments included therein. Furthermore, a signal switching device satisfying any desired object or application can be formed by suitably selecting the number coordinate axes or by dividing the device structure into any suitable number of groups which are to be switchably connected via the determined numbers of inlets and outlets.

Another feature of this invention is that since all of the inlets, outlets, and interconnection means are disposed in predetermined, respective directions, connections can be established by utilizing printed circuitry, or by utilizing tape cable" in which a plurality of parallel conductors arranged in a plane are imbedded in a tape of insulating material. This assures ease of wiring and hence, permits automatic wiring of the switching device. Furthermore, since the inlets, outlets, and interconnection means exhibit mutually orthogonal relationships, the amount of undesired crosstalk can be reduced to a minimum. In particular, since any two switching segment groups to be switchably connected are physically interconnected with linkage wires which extend in a predetermined direction, the distance between any two segment groups, as well as the crosstalk attenuation between switched information signals can be reduced to a minimum. Therefore, a signal switching device with a minimum number of switching elements can be realized as will be described.

These and other features and effects of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, wherein:

I FIG. 1 is a schematic diagram illustrating the connections of a conventional signal switching device;

FIG. 2 is a transverse cross sectional view of an embodiment of a signal switching element;

FIG. 3 is a sectional view of the element taken along lines l4l4 of FIG. 2;

FIG. 4 is a graphical representation of the signal switching element;

FIG. 5 is a plan view of a first embodiment of a segment of switching elements;

FIG. 6 is a front view of the segment shown in FIG. 5;

FIG. 7 is a right side view of the segment shown in FIG. 5;

FIG. 8 is a plan view of a second embodiment of a segment of switching elements;

FIG. 9 is a front view of the segment shown in FIG. 8;

FIG. 10 is a right side view of the segment shown in FIG. 8;

FIG. 11 is a plan view of a signal switching device;

FIG. 12 is a front view of the signal switching device shown in FIG. 11;

FIG. 13 is a bottom view of the signal switching device shown in FIG. 11;

FIG. 14 is a Z-axis exploded view of a signal switching device in accordance with this invention;

FIG. 15 is a schematic diagram illustrating the connections of the signal switching device shown in FIG. 14; and

FIGS. 16 through 18 schematically show perspective views of signal switching devices in accordance with other embodiments of this invention.

Now a description will be given of a conventional signal switching device by reference to FIG. 1. As illustrated, signal switching matrices P P P and P each containing a set of 4 X 4 crosspoints, are provided as a primary switching stage. Matrix P is comprised of inlets X X X and X and outlets Y Y Y and Y03 which intersect these inlets. Likewise, matrices P P and P are comprised respectively of inlets X X 12, 13 and Outlets m, u, 12 rs; 20, 21 22, 23 and Y2), Y2], Ygg, and X30, X31, X32, X33 and Yao, Y Y Y Switching matrices S S S and S similar to the aforementioned primary switching stages, contain 4 X 4 arrays of crosspoints, and are provided as the secondary switching stage. S0, S S2, and 8;, are comprised respectively of inlets X00, X01, X02, X03, and outlets Y00,Y01, Yoz, Yog X10, X11, X12, X13 and io, n, iz, rs; 20, 21, X22, 23 and 20, 21, 22, Y23; and X30, 31, 32, 33 and 30, sr, sz, a3-

The outlets Y Y Y and Y03 of the primary stage switching matrix P are respectively connected to the inlets X0 X 0, X 0, and X 0 of the secondary stage switching matrices S0, S1, S2, and S Similarly, the outlets Y Y T and Y of the switching mat ix P1 a sp ve y qnn dlalh ifl X0 X X21, and X of the switching matrices S0, S S2, and S Furthermore, the outlets Y20, Y21, Y and Y23 of the switching matrix P and the outlets Y3(), Y Y and Y of the switching matrix P3 are respectively connected to X02, 12, 22,

Xaai 194 I0 X00, X13, X20, X3 of the switching intersecting crosspoints of said inlets and outlets. For

instance, on closure of the switching contacts identifiable as (X Y and (X,,,, Y,,,,'), a signal path is established from inlet X of the primary switching stage to outlet Y of the secondary switching stage. It has been known with such a conventional signal switching device, that a path from a desired one of the inlets 00 01, 02, 03 10 11, 12 13, 20 21, 22 X X X X and X to a desired one of the outlets YOU) Ol a YOZI, OB a l0 1 ll a YIZ Y13, Y2O 2I a Y Y Y;,,,, Y;,,', Y and Y;,;,' can be established with a minimum number of switching elements. For this purpose, a switching device consisting of the illustrated switching matrices as a functional and structural unit containing a plurality of switching elements, the outlets of the primary stage switching matrices P P P and P are connectable to the inlets of the secondary stage switching matrices S S S and 5;, by means of linkage wires. Consequently, in cases where these switching matrices are arranged in the same plane, the linkage wires connected between the outlets of the primary stage switching matrices P P P and P and the inlets of the secondary stage switching matrices S S S and S intersect one another in the same plane in a similar manner as the linkage wire between the outlet Y and the inlet X intersects the linkage wire between the outlet Y and the inlet X Accordingly, it is inadvisable to use noninsulated conductors for wiring these linkage connections and further, the effort expended in wiring these points of intersection becomes extremely complex when the number of linkage wires becomes large. Furthermore, the fact that the linkage wires intersect one another in the aforedescribed manner makes it extremely difficult to limit the length of linkage wires or to reduce the space occupied by the linkage wires.

The signal switching device according to this invention is comprised of segments, the segment constituting the basic structural and functional unit, each segment containing a plurality of signal switching elements. A magnetic latching type reed switch, for example, may be used for the signal switching element. Alternatively, an electronic switch such as a transistor or a switchable ferrite core may be utilized as a switching element. The magnetic latching type reed switch may include a pair of sealedin-glass contacts 1 and 2 disposed parallel to each other as shown in FIGS. 2 and 3, and a pair of terminals 3 and 4 disposed at opposite end portions of sealed contact 1. Similarly a pair of terminals 5 and 6 are disposed at opposite end portions of sealed contact 2. If desired, the sealed contact 2 may be omitted and the reed switch may include only a single contact 1. Plates 7 and 8 formed of magnetically semi-hard material, are disposed so as to sandwich the sealed contacts l and 2, and an operating coil 9 is wound about the plates 7 and 8 for controlling the direction of magnetization in these plates 7 and 8. Furthermore, a shunt. plate 10 of magnetically semi-hard material is provided near the mid-point in the longitudinal direction of the sealed contacts 1 and 2, and cooperates with plates 7 and 8 to determine a magnetic path.

The operation of signal switching element 11 has been well known in the art. Therefore, a detailed description is abbreviated herein for simplicity. The symbol for the signal switching element 11 is indicated by the mark X at the point of intersection of two orthogonally intersecting conductors 12 and 13 as shown in FIG. 4. The make side and break side terminals or input and output terminals, 3 and 4, respectively, (or 5 and 6) of the signal switching element 11 correspond respectively to conductors 12 and 13.

Each segment consists of a .plurality of such signal switching elements 11. For instance, as shown in FIGS. 5 through 7, the segment 15 is comprised of a rectangular parallelepiped case 16 which may be made of synthetic resin, for example, and four signal switching elements 11a, 11b, 11c, and 11d enclosed therein with respective sealed contacts aligned and in parallel relation with respect to each other. If desired, case 16 may adopt an alternative polyhedron configuration. The make side contact terminals 3a, 5a, 3b, 5b, 30, 5c, 3d, and 5d of switching elements 11a, 11b, 11c, and 11d project respectively from the top surface 16a of the case 16. Terminals 3a, 3b, 3c, and 3d are mutually aligned and disposed parallel to mutually aligned terminals 5a, 5b, 5c, and 5d forming an array on the top surface 16a. Similarly, break side contact terminals 4a, 6a, 4b, 6b, 4c, 60, 4d and 6d project outward respectively from the bottom surface 16b which is parallel to the top surface 16a and are disposed in an opposite direction to that of the respective make side contact terminals. Thus, the break side contact terminals 4,6 comprise a planar array that is parallel to and spaced from the array formed by make side contact terminals 3,5.

Segments assuming other geometric configurations of contact terminals may also be provided such, for example, as one having an array of terminals projecting outward from each of two adjacent orthogonal surfaces. As shown in FIGS. 8 throughlO, auxiliary terminals 4a, 6a, 4b, 6b, 40', 6c, 4d, and 6d, comprise an array disposed in the same manner as terminals 3a, 5a, 3d, and 5d, and are provided on the side surface 16c orthogonal to the case top surface 16a on which the make side contact terminals are provided and further, these auxiliary terminals are respectively connected internally by suitable conducting means to terminals 4a, 6a 4b, 6b, 4e, 6c, 4d, and 6d. The terminals 4a through 4d and 6a through 6d are such that the spaced intervals between successive terminals are the same. The terminals 4a through 6a are similarly spaced. In addition, the terminals 4a-4d and 4a-4d are disposed along axes parallel to the axes passing through terminals 6a-6d and 6a6d', respectively. With this kind of segment, flangelike projections 17 and 18 are provided at opposite ends of the case 16 to form a unitary structure therewith; and two notches 19 and 20, whose width is slightly larger than the separation between the two sets of aligned terminals 3a through 3d and 5a through 5d, are provided in the flangelike projections on the top surface 16a. The projections 17 and 18 extend around the circumference of the end portion of case 16 and should be slightly higher than the height of the outwardly projecting terminals 3a-3d, 5a-5d, 4a-4d and 6 .11%,Ihqsttqrm a st a. thr hrfl. 6 to which auxiliary terminals 4a, 6a through 4d, 6d are connected, do not project beyond the flangelike projections 17 and 18 of the case 16 as illustrated in FIG. 10.

A simple structure of a signal switching device comprised of these kinds of segments will now be described by reference are projected FIGS. 11 through 13. According to this embodiment, four segments 15A, 15B, 15C, and 15D are mounted on a printed circuit board 22 so as to be adjacent and parallel to one another, thereby forming an array of signal switching elements. It should herein be noted that each switching element of the array may include a reed switch having a single pair of terminals such as 3,4, rather than the two pair of terminals 3,4 and 5,6 illustrated. Terminals b, is in terminal section on one surface of these segments 15A, 15B, 15C and 15D, for instance break contact terminals 4 and 6, are projected outward from the bottom surface of the printed circuit board 22 through small holes provided in the printed circuit board 22. On the bottom surface of the board 22, there are provided a conductor 23a for connection to terminals 4a of segments 15A, 15B, 15C, and 15D, a conductor 24a for connection to terminals 6a thereof, a conductor 23b for connection to terminals 4b thereof, and conductors 24b, 23c, 24c, 23d, and 24d respectively, for connection to terminals 6b, 4c, 60, 4d and 6d. In other words, each of the conductors 23a, 24a, 23b, 24b, 23c, 24c, 23d, and 2411 is in multiple connection with the corresponding break contact terminals. The aforedescribed conductors are disposed parallel to one another any may be printed on the board 22 in a conventional manner such that a portion of the board on one side constitutes a terminal section 27 on which terminals 25a, 26a, 25b, 26b, 25c, 26c, 25d, and 26d are connected to corresponding conductors. This geometrical configuration comprised of a plurality of segments and mutually interconnected with conductors so as to form an array of signal switching elements, can be considered the structural unit of a signal switching device according to this invention.

The segments 15 can be arranged not only in the one direction shown in FIGS. ll-13, but also in threedimensional form. FIG. 14 illustrates a signal switching device comprised of four segments 15 having their long sides directed along the Z axis and stacked in the X direction, four stacks of segments disposed successively along the Y axis, and two segments disposed successively along the Z axis. The X-Y-Z directions illustrated in FIG. 14 are merely exemplary and the axes are freely interchangeable. The three-dimensional unitary structure composed of the segments can be separated into two parts along the X axis to constitute two segment groups such as a primary switching stage and a secondary switching stage, different in function and designated PSW and SSW, respectively. The former segment group PSW is comprised of a first set of segments P P P and P stacked in the X direction and three other sets of segments P P P P P P P P and P and P P P disposed in succession in the Y direction with respect to the set of P P P and P Likewise, the latter segment group SSW is comprised of a first set of segments S S S and S stacked in the X direction and three other segmems 01 11 21; 31 02 12 S 22 32 03 13 23 33 disposed side by side in the Y direction with respect to the set of S S S and S The latter segment group SSW is comprised of segments provided with the aforedescribed auxiliary terminals. It should be understood that the number of segments utilized and the number of signal switching elements in each segment may be any convenient numbers.

On one surface of a set of segments such as the first set P P P and P in the segment group PSW, i.e., on the side through which break terminals 4 and 6 for example project, a printed circuit board 22pa as described in connection with FIGS. 11 through 13 is provided. Conductors 23a, 24a, 23b, 24b, 23c, 24c, and 23d, 24d printed on the printed circuit board 22pa are aligned in the X direction respectively as inlets X X X02, and X In a similar position on the second set of segments P P P and P printed circuit board 22pb is provided and inlets X X X and X are provided as conductors. Similarly printed circuit boards 22pc and 22pd are provided respectively for the third set of segments P P P P and the fourth set of segments P P P P From these printed circuit boards 2212c and 22pd, inlets X X X Xhd 23 and inlets X X X X are respectively derived On the surface through which make terminals 3 and 5 of the first set of segments S S S and S in the sement group SSW project, a printed circuit board 22sa, similar to the one described in connection with FIGS. 11 through 13, is provided. This printed circuit board 22sa is provided with conductors 27a, 27b, 27c and 27d (not shown) respectively, in multiple connection with the make terminals 3a, 3b, 3c, and 3d associated with these segments and in addition, conductors 28a, 28b, 28c, and 28d (not shown) are provided to which the make terminals 5a, 5b, 5c, and 5d are connected, respectively. These conductors 27a, 28a, 27b, 28b, 27c, 28c, 27d, 28d are aligned in the Y direction as outlets Y' Y Y' and Y In like manner, printed circuit boards 22sb, 22sc, and 22sd are provided, respectively,

Y direction.

An additional printed circuit board M is provided for interconnecting the make contact terminals of the segment P and the auxiliary terminals of the segment S The printed circuit board M is provided with a conductor 30a for connection between the make contact terminals 3 and the auxiliary terminals 4, and a conductor 31a is provided for connection between the make contact terminals 5 and the auxiliary terminals 6'. These conductors 30a and 31a constitute a linkage wire L extending in the Z direction. In a similar manner, a printed circuit board M is provided so as to interconnect the make contact terminals of the segment P and the auxiliary terminals of segment S and on this board M a linkage wire L is provided. Likewise, printed circuit boards M M M M 12 13 20 21, 22, 23, 30 M31 32 and 33 are respectively provided so as to cover thefull lengths of paired segments P and S and P and S P and 01, u and 11, 12 and 21, 13 and 31, 20 and 02 om zi and 12, 22 and 22, 23 and 32 s0 and 03, P31 and S P and S and P and S and further, the linkage Wires 02 03, L10 11 12, L13! zoi 21 22 23 L L L and L are respectively aligned on these printed circuit boards.

The segment groups PSW and SSW have been separated from each other in the illustration of FIG. 14 merely fro ease of understanding, but actually they are united to form a unitary structure. Furthermore, all of the above-mentioned printed circuit boards M are understood to be provided although most of them are not shown in the illustration.

FIG. 15 is a schematic diagram illustrating the connections of the signal switching device of FIG. 14, wherein single lines are used to indicate the interconnections between pairs of segments P and S P and S P and S and P and S although pairs of interconnections may be used. Similar interconnecting relationships for segments P and S P and S P and S P and S and so forth are also illustrated in FIG. 15. Consequently, the signal switching device of FIG. 14 will become a l6 l6 matrix with 16 inlets (X X and 16 outlets (Y' Y as a whole as will be apparent from the corresponding illustration of FIG. 15. As will be evident from a comparison between FIG. 15 and FIG. 1, or from an inspection of FIG. 14, the inlets X' X' and X of each of the secondary stage switches S S and S in FIG. 1 have been rearranged on the linear extension of the outlets Y Y and Y of the primary stage switch P but the electrical connections have been maintained. Further, the inlets X' X and X' of each of the secondary stage switches S S and S of FIG. 1 have been rearranged on the linear extension of the outlets Y Y and Y of the primary stage switch P while maintaining the original electrical connections. Similarly, the inlets of each of the secondary stage switches S S S and S have been rearranged on the linear extension of the outlets of each of the primary stage switches P and P Thus, it is seen the signal switching device of FIG. 14 performs an operation equivalent to the conventional device shown in FIG. 1 and admits of ready application with digital computers, data processing equipment, communication switching equipment and the like.

With the signal switching device according to this invention shown in FIG. 14, the inlets X through X are disposed in parallel relation to one another, as are the interconnection means L through L and the outlets Y through Y It will be seen from this embodiment that the inlets, interconnection means and outlets can be formed on respective printed circuit boards. This permits ease. of automatic connections for the inlets, the outlets, the interconnection means, and their as sociated terminals. All of the segments of the segment group PSW are geometrically aligned with the corresponding segments of the group SSW. Accordingly,

the interconnection means L through L which correspond to the linkage wires of the conventional device shown in FIG. 1 are integrated into the unitary structure of PSW and SSW, such that these interconnections can be established in a single operation. With the conventional device shown in FIG. 1, plural connecting steps were necessary, because the outlets of the primary stage switches which were connected to crosspoint terminals and the inlets of the secondary stage switches which were connected to crosspoint terminals had to be further connected with linkage wires to establish interconnection between the inlets and the outlets.

It will be obvious from the foregoing that the switching capacity of a signal switching device can be readily controlled by increasing or decreasing the number of segments in the X or Y direction or both directions, of either or both of segment groups PSW or SSW as illustratively presented in FIG. 14. For example, at a segment group PSW a switching matrix of 32 X 16 crosspoints can be realized by adding still another segment group PSW (not shown) in Z direction and corresponding linkage wires (L L for extending the necessary connections.

It is seen that the inlets X through X the outlets Y' through Y and the interconnection means L through L extend respectively along the X, Y, and Z axes. Since these conductors intersect substantially at right angles, noise signals due to mutual inductance therebetween are suppressed to a minimum and the amount of crosstalk is greatly reduced. Moreover, the segment groups PSW and SSW can be physically positioned in close proximity such that the linkage wires share no points of intersection. This assures excellent electrical transmission characteristics such as low transmission loss, improved crosstalk attenuation response, and wider operating frequency bandwidth.

Although not shown in FIG. 14, the printed circuit boards 22pa through 22pd and 22sa through 22sd can be mounted in a support frame by inserting opposite edges of each board into pairs of guide slots provided in the support frame whereby the relative positions of the segments in the illustrated segment groups remain as shown. In this case, the terminal sections 27 of the printed circuit boards can be plugged into multi-lead jacks provided in the support frame so as to permit connections with other equipment.

The device shown in FIG. 14 is composed of a plurality of segment units, each unit comprised of four segments. Such a segment unit can also be represented as a 10 basic structural unit of the switching device. While a particular embodiment is illustrated in FIG. 14, in which printed circuit boards are used for terminal connections of the inlets, outlets, and interconnection means, conventional tape cable may be utilized in another embodiment. The tape cable consists of a thin, flexible film of insulating material and a plurality of parallel conductors laid on or imbedded in the film along the longitudinal direction'thereof. An embodiment of a signal switching device using the tape cable is illustrated in FIG. 16. As illustrated therein, the printed circuit boards 22pa through 22pc and 22sa through 22sc of FIG. 14 are replaced with tape cables denoted by corresponding reference characters 33pa through 33pc and 33sa through 3386. Conductors 30 and 31 are directly connected as by wires without using interconnection means such as the printed circuit boards M through M and segments provided with flangelike projections 17 and 18 as previously illustrated in FIGS. 8 through 10 are employed.

Although a switching device comprised of two segment groups has thus far been described, it is contemplated that more than two segment groups may comprise a unitary switching device. For instance, an embodiment shown in FIG. 17 illustrates a switching device divisible into two parts along the X axis, the lower part of the structure is divisible into two segment groups 40 and 41 along the Y axis and further, the upper part is divisible into two segment groups 42 and 43 along the Z axis. Furthermore, the divisibility of a switching device by a single plane is by no means a limiting condition. This invention encompasses the possibility of dividing a switching device into a plurality of parts by a combination of planes 45, 45, 45" which intersect orthogonally to one another to form segment groups 46 and 47 as illustrated in FIG. 18.

Thus, it is seen, the structures contemplated by this invention consist generally of l, m, and n segments disposed in succession along X, Y, and Z rectangular coordinate axes, each segment containing a plurality of switching elements. Each of l, m, and n should be a positive integer equal to or larger than unity, and at least one of them should be equal to or larger than 2. Furthermore, the switching device may be divided into a plurality of segment groups and when any two groups are taken into consideration, inlets are derived from one group in a first direction, such as for example, the X direction, outlets are derived from the other group in a second direction, orthogonal to the first, such as the Y direction, and interconnection means for connecting the two groups are derived in a third direction, orthogonal to said first and second directions, such as the Z direction. The numbers of inlets, outlets, and interconnection means are, respectively, a, b, and 0 (each of them being a positive integer equal to or larger than unity), and are in multiple connection with the terminals of the switching elements included in the segments. Although the invention has been described with particular reference to a switching element comprised of a magnetic latching type reed switch, it will be evident that any other suitable element such as a semiconductor switching element, a ferrite core, or the like may be used. If a reed switch is adopted, it may include a single make terminal and a single break terminal, or a plurality of make and break terminals as hereinbefore described. What is claimed is:

l. A signal switching device, comprising:

a plurality of each of first and second groups of rectangular parallelopiped switching units arranged in X, Y and Z directions;

each of said first groups having said units thereof arranged in stacks in said X direction with respective lengthwise axes positioned in parallel in said Z 1 direction; said first unit group stacks disposed sideby-side in said Y direction;

each of said second groups having said units thereof arranged in stacks in said X direction with respective lengthwise axes positioned in parallel in said Z direction; said second unit group stacks disposed side-by-side in said Y direction;

each of said first group units including a plurality of each of said second group units including a plurality a pairs of switches disposed lengthwise of each of said last-mentioned units; each of said second group switches having a make terminal and an auxiliary break terminal; each of said unit switches of said second group disposing said make terminals a plurality of first groups of spaced parallel conductors disposed in said -X direction in said respective spaced X-Z planes of said first group units for multiply connecting of said break terminals of corresponding switches in said respective first group unit stacks;

a plurality of second groups of spaced parallel conductors disposed in said Y direction in said respective Y-Z planes for multiply connecting said make terminals of corresponding switches of said second group units in said Y-Z planes;

input signal lines disposed in parallel and connected to said break terminals of said switches in said respective first group units in said X-Z planes; and

output signal lines disposed in parallel and selectively connected to said make terminals of said switches of said second group units in said Y-Z planes;

whereby a desired one of said input signal lines is connectable to a desired one of said output lines. 

1. A signal switching device, comprising: a plurality of each of first and second groups of rectangular parallelopiped switching units arranged in X, Y and Z directions; each of said first groups having said units thereof arranged in stacks in said X direction with respective lengthwise axes positioned in parallel in said Z direction; said first unit group stacks disposed side-by-side in said Y direction; each of said second groups having said units thereof arranged in stacks in said X direction with respective lengthwise axes positioned in parallel in said Z direction; said second unit group stacks disposed side-by-side in said Y direction; each of said first group units including a plurality of pairs of switches disposed lengthwise of each of said last-mentioned units; each of said switches having a make terminal and a break terminal; each of said unit switches of said first group disposing said make terminals on one side of each of said lastmentioned units and said break terminals on a side of each of said last-mentioned units opposite to said one side; whereby said first group units stacked and disposed in said respective X and Y directions position said make and break terminals in alternate parallel X-Z planes; each of said second group units including a plurality a pairs of switches disposed lengthwise of each of said last-mentioned units; each of said second group switches having a make terminal and an auxiliary break terminal; each of said unit switches of said second group disposing said make terminals on one side of each of said last-mentioned units and said auxiliary break terminals on a side orthogonal to said lastmentioned one side; whereby said second group units stacked and disposed in said respective X and Y directions position said auxiliary break terminals in spaced parallel X-Z planes and said make terminals in spaced parallel Y-Z planes; a plurality of pairs of spaced parallel conductors disposed in the Z direction for multiple connecting said make terminals of said first group switch units and corresponding auxiliary break terminals of said second group switch units in said X-Z planes; a plurality of first groups of spaced parallel conductors disposed in said X direction in said respective spaced X-Z planes of said first group units for multiply connecting of said break terminals of corresponding switches in said respective first group unit stacks; a plurality of second groups of spaced parallel conductors disposed in said Y direction in said respective Y-Z planes for multiply connecting said make terminals of corresponding switches of said second group units in said Y-Z planes; input signal lines disposed in parallel and connected to said break terminals of said switches in said respective first group units in said X-Z planes; and output signal lines disposed in parallel and selectively connected to said make terminals of said switches of said second group units in said Y-Z planes; Whereby a desired one of said input signal lines is connectable to a desired one of said output lines. 